Google seems to have stopped appending UTM parameters on Gemini links, the cited URLs in Gemini's AI responses. Google started adding UTM parameters to links in Gemini in early September, but then, around September 28th, Google stopped.
Natzir has been following this closely and he shared a graph showing how Gemini's UTM tags grew for three weeks but then vanished overnight. The UTM parameter was utm_source=gemini but I do not see them on any Gemini links anymore.
Here is that chart he shared on X: Google does still pass the referrer data from the desktop version of Gemini and he said visits with a gemini.google.com referer stayed flat the whole time. But Google seems to have removed the UTM parameters it started adding in September.
John Mueller from Google even commented on Reddit that he saw the UTM parameters on Gemini links a month or so ago.
Not just me. @Xyborg sees the same drop around Sep 28 in Gemini's answers! The cited URLs stopped carrying utm_source
https://t.co/mCXJAy11c4 ☝️ I've added it to my post on the state of AI traffic measurement
cc: @rustybrick
— Natzir (@natzir9)October 27, 2026 It does still pass referrer:
@Xyborg @rustybrick On web, yes. From the iOS app, no. It opens links in its own WebView and sends no referrer, so in GA4 it lands in Direct. The only trace is the GeminiiOS user agent in server logs, the one I found and @rustybrick covered: https://t.co/c750oAz0U1
New test 👇 iOS app vs Web App https://t.co/QMFA7QnOdP
— Natzir (@natzir9)[October 28, 2026](https://x.com/natzir9/status/2115404736266666451?ref_src=twsrc%5Etfw)
Forum discussion at [X](https://x.com/natzir9/status/2115404736266666451).